foo.cc: In function 'void hanoi(int, char, char, char)':
foo.cc:7:40: warning: array subscript has type 'char' [-Wchar-subscripts]
    7 |                 printf("%d %c %c\n", a[x], x, z);
      |                                        ^
foo.cc:11:40: warning: array subscript has type 'char' [-Wchar-subscripts]
   11 |                 printf("%d %c %c\n", a[x], x, z);
      |                                        ^

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